Mild Synthesis of mono-, bis- and tris 1,2-Dihydrobenzo[4,5]imidazo[1,2- a]pyrimidine Derivatives Using Alkyl Disulfamic Acid Functionalized Magnetic Nanoparticles

Alkyl disulfamic acid-functionalized silica-coated magnetic nanoparticles (ADSA-MNPs) have been synthesized as a hybrid organic- inorganic acidic nanoparticles and its catalytic activity has been evaluated in the synthesis of mono-, bis- and tris 1,2-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidine via a one-pot three, pseudo-five or pseudo-seven component condensation reaction of aromatic aldehydes, malononitrile and 2-aminobezimidazole under solvent-free heating. The heterogeneous catalyst was facilely separated from the reaction mixture by utilizing external magnetic field and reused for several times without considerable decrease of catalytic performance.